denison



G H DE 2Sheets-Sheet1.

- Indexes.

No. 197.345. Patented Nov. 20. I877.

'lM PRovEw fl 1N, INDEXES.

IBAYLOITY, MICHIGAN.

.Specification forming part of Letters Patent No. 197,345, dated November 20,1877; PPl ejJion filed rf ovember 9,

' To all whom it may concern:

Beit known that I, CHARLES H. DENISON, of Bay City, in the county of Bay and State of Michigan, have invented a new and useful Improvement in the Methodof IndexingBooks, which is applicable to dictionaries, encyclopedias, digests, concordances, directories, and all books alphabetically arranged, to ledgers and blanlebooks, also to the Bible, and all works divided into chapters or comprising different subjects, of which the following is a specification: r

I The invention consists in segmental recesses cut into the edges of the leaves adjacent to the page bearing the matter to be indicated, in

such manneras to expose to view a small portion of such page, andno other leaf or page surface except such portion as is desired to be indicated. On said exposed surface is printed the letter, figure, word, or character best calculated to serve as a reference to the matter on said page. This process is repeated for each letter or subject comprised in the book,

and theletters or characters, placed as above described, are visible when the book is closed as well as when it is open.

The recesses may be cut in either direction; but the best results are attained, aswill be presently seen, by cutting from the middle of the book toward the two covers. In books of ordinary size the recesses should be cut in two series, as in the diagrams; but in books of considerable length, as, blank-books, the segments may 'be arranged, in a single series, changing the direction of the cuttings at the middle of the book. The best method, however, is to place the segments in two series in single volumes, and duplicating this arrangement in-volumes comprising two or morebooks.

The diagrams accompanying this specification represent a lexicon with the index applied, and Figure 1 represents the book open at the middle, showing all the letters in the cuttings or segments.

The next feature of the invention is the placing, on the outside face of the front and back I in the recesses may be called primary, and the other letters secondary, the latter being used as guides to the recesses.

When the book is lying closed on either side, the primaries of the lower series only are visible, as is shown by Figs. 3 and 4, and the book can be opened to any letter of that series by a single movement, while the secondaries on the upper cover furnish the same facility in opening to any desired letter of the upper series.

Suppose the book to be lying closed, with its front cover upward, as in Fig. 3, and it is desired to open it to 0, pass the finger directly under that letter on the cover into its corresponding recess, and the book is opened by a single movement to the position represented.

by Fig. 2. Here is displayed the third feature of the invention. In this figure only the first three primaries, A, B, and O, of the first series are visible; but the secondaries of the rest of that series appear on the right-hand margin, each pointing to its respective recess.

The secondaries, as will be readily inferred, are placed not only on the covers, but also on the corresponding side of every leaf throughout the book, so that, whether the book be lying on either side or open to any page, the student can open to any desired letter by a single movement.

The reason, why W appears as the last letter is because the subsequent letters are all found at the same opening.

The primary letters may be printedon the leaf-surface of the recesses. To secure this surface against soil or abrasion, a thin scale of isinglass may be pasted onit, so that'the letter will be fully protected while still remaining clearly visible.

. Another method of protecting said surfaces is bycovering them with a facing of leather bearing the letter, figure, or character, and when this facing is of black morocco bearing a gold letter, it adds materially to the orna- I mental appearance of the book.

What I claim is-- y Y 1. A book the front edge or ends of which are provided with one or more series of segmental recesses, out substantially in the man= ner described in the foregoing specification, each recess cut to the leaf to be indicated, said leaves, on their exposed part, bearing the'apu scribed in the foregoing specification, each l cess cut to the leaf to be indicated, said leaves,

fi seisexnoseerm tteslna ne, crchamtealettemlname, or

character being also placed on the opposite 4 side of said leaves, and of all the leaves in the book on the same side of the recesses directly jonpesit wrnespepdnigg recesses, so that when the book is open at aii'y'page the student can turn to any desired letter, name, or char- 1 by asiggla mption, substantially as described.

OHARLES H. DENISON. Witnesse GEO. F. GRAHAM, H. P. SANDERS. 

